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/*! \file exif-data.h
* \brief Defines the ExifData type and the associated functions.
*/
/*
* \author Lutz Mueller <lutz@users.sourceforge.net>
* \date 2001-2005
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301 USA.
*/
#ifndef __EXIF_DATA_H__
#define __EXIF_DATA_H__
#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */
#include <libexif/exif-byte-order.h>
#include <libexif/exif-data-type.h>
#include <libexif/exif-ifd.h>
#include <libexif/exif-log.h>
#include <libexif/exif-tag.h>
/*! Represents the entire EXIF data found in an image */
typedef struct _ExifData ExifData;
typedef struct _ExifDataPrivate ExifDataPrivate;
#include <libexif/exif-content.h>
#include <libexif/exif-mnote-data.h>
#include <libexif/exif-mem.h>
/*! Represents the entire EXIF data found in an image */
struct _ExifData
{
/*! Data for each IFD */
ExifContent *ifd[EXIF_IFD_COUNT];
/*! Pointer to thumbnail image, or NULL if not available */
unsigned char *data;
/*! Number of bytes in thumbnail image at \c data */
unsigned int size;
ExifDataPrivate *priv;
};
/*! Allocate a new #ExifData. The #ExifData contains an empty
* #ExifContent for each IFD and the default set of options,
* which has #EXIF_DATA_OPTION_IGNORE_UNKNOWN_TAGS
* and #EXIF_DATA_OPTION_FOLLOW_SPECIFICATION set.
*
* \return allocated #ExifData, or NULL on error
*/
ExifData *exif_data_new (void);
/*! Allocate a new #ExifData using the given memory allocator.
* The #ExifData contains an empty #ExifContent for each IFD and the default
* set of options, which has #EXIF_DATA_OPTION_IGNORE_UNKNOWN_TAGS and
* #EXIF_DATA_OPTION_FOLLOW_SPECIFICATION set.
*
* \return allocated #ExifData, or NULL on error
*/
ExifData *exif_data_new_mem (ExifMem *);
/*! Allocate a new #ExifData and load EXIF data from a JPEG file.
* Uses an #ExifLoader internally to do the loading.
*
* \param[in] path filename including path
* \return allocated #ExifData, or NULL on error
*/
ExifData *exif_data_new_from_file (const char *path);
/*! Allocate a new #ExifData and load EXIF data from a memory buffer.
*
* \param[in] data pointer to raw JPEG or EXIF data
* \param[in] size number of bytes of data at data
* \return allocated #ExifData, or NULL on error
*/
ExifData *exif_data_new_from_data (const unsigned char *data,
unsigned int size);
/*! Load the #ExifData structure from the raw JPEG or EXIF data in the given
* memory buffer. If the EXIF data contains a recognized MakerNote, it is
* loaded and stored as well for later retrieval by #exif_data_get_mnote_data.
* If the #EXIF_DATA_OPTION_FOLLOW_SPECIFICATION option has been set on this
* #ExifData, then the tags are automatically fixed after loading (by calling
* #exif_data_fix).
*
* \param[in,out] data EXIF data
* \param[in] d pointer to raw JPEG or EXIF data
* \param[in] size number of bytes of data at d
*/
void exif_data_load_data (ExifData *data, const unsigned char *d,
unsigned int size);
/*! Store raw EXIF data representing the #ExifData structure into a memory
* buffer. The buffer is allocated by this function and must subsequently be
* freed by the caller using the matching free function as used by the #ExifMem
* in use by this #ExifData.
*
* \param[in] data EXIF data
* \param[out] d pointer to buffer pointer containing raw EXIF data on return
* \param[out] ds pointer to variable to hold the number of bytes of
* data at d, or set to 0 on error
*/
void exif_data_save_data (ExifData *data, unsigned char **d,
unsigned int *ds);
void exif_data_ref (ExifData *data);
void exif_data_unref (ExifData *data);
void exif_data_free (ExifData *data);
/*! Return the byte order in use by this EXIF structure.
*
* \param[in] data EXIF data
* \return byte order
*/
ExifByteOrder exif_data_get_byte_order (ExifData *data);
/*! Set the byte order to use for this EXIF data. If any tags already exist
* (including MakerNote tags) they are are converted to the specified byte
* order.
*
* \param[in,out] data EXIF data
* \param[in] order byte order
*/
void exif_data_set_byte_order (ExifData *data, ExifByteOrder order);
/*! Return the MakerNote data out of the EXIF data. Only certain
* MakerNote formats that are recognized by libexif are supported.
* The pointer references a member of the #ExifData structure and must NOT be
* freed by the caller.
*
* \param[in] d EXIF data
* \return MakerNote data, or NULL if not found or not supported
*/
ExifMnoteData *exif_data_get_mnote_data (ExifData *d);
/*! Fix the EXIF data to bring it into specification. Call #exif_content_fix
* on each IFD to fix existing entries, create any new entries that are
* mandatory but do not yet exist, and remove any entries that are not
* allowed.
*
* \param[in,out] d EXIF data
*/
void exif_data_fix (ExifData *d);
typedef void (* ExifDataForeachContentFunc) (ExifContent *, void *user_data);
/*! Execute a function on each IFD in turn.
*
* \param[in] data EXIF data over which to iterate
* \param[in] func function to call for each entry
* \param[in] user_data data to pass into func on each call
*/
void exif_data_foreach_content (ExifData *data,
ExifDataForeachContentFunc func,
void *user_data);
/*! Options to configure the behaviour of #ExifData */
typedef enum {
/*! Act as though unknown tags are not present */
EXIF_DATA_OPTION_IGNORE_UNKNOWN_TAGS = 1 << 0,
/*! Fix the EXIF tags to follow the spec */
EXIF_DATA_OPTION_FOLLOW_SPECIFICATION = 1 << 1,
/*! Leave the MakerNote alone, which could cause it to be corrupted */
EXIF_DATA_OPTION_DONT_CHANGE_MAKER_NOTE = 1 << 2
} ExifDataOption;
/*! Return a short textual description of the given #ExifDataOption.
*
* \param[in] o option
* \return localized textual description of the option
*/
const char *exif_data_option_get_name (ExifDataOption o);
/*! Return a verbose textual description of the given #ExifDataOption.
*
* \param[in] o option
* \return verbose localized textual description of the option
*/
const char *exif_data_option_get_description (ExifDataOption o);
/*! Set the given option on the given #ExifData.
*
* \param[in] d EXIF data
* \param[in] o option
*/
void exif_data_set_option (ExifData *d, ExifDataOption o);
/*! Clear the given option on the given #ExifData.
*
* \param[in] d EXIF data
* \param[in] o option
*/
void exif_data_unset_option (ExifData *d, ExifDataOption o);
/*! Set the data type for the given #ExifData.
*
* \param[in] d EXIF data
* \param[in] dt data type
*/
void exif_data_set_data_type (ExifData *d, ExifDataType dt);
/*! Return the data type for the given #ExifData.
*
* \param[in] d EXIF data
* \return data type, or #EXIF_DATA_TYPE_UNKNOWN on error
*/
ExifDataType exif_data_get_data_type (ExifData *d);
/*! Dump all EXIF data to stdout.
* This is intended for diagnostic purposes only.
*
* \param[in] data EXIF data
*/
void exif_data_dump (ExifData *data);
/*! Set the log message object for all IFDs.
*
* \param[in] data EXIF data
* \param[in] log #ExifLog
*/
void exif_data_log (ExifData *data, ExifLog *log);
/*! Return an #ExifEntry for the given tag if found in any IFD.
* Each IFD is searched in turn and the first containing a tag with
* this number is returned.
*
* \param[in] d #ExifData
* \param[in] t #ExifTag
* \return #ExifEntry* if found, else NULL if not found
*/
#define exif_data_get_entry(d,t) \
(exif_content_get_entry(d->ifd[EXIF_IFD_0],t) ? \
exif_content_get_entry(d->ifd[EXIF_IFD_0],t) : \
exif_content_get_entry(d->ifd[EXIF_IFD_1],t) ? \
exif_content_get_entry(d->ifd[EXIF_IFD_1],t) : \
exif_content_get_entry(d->ifd[EXIF_IFD_EXIF],t) ? \
exif_content_get_entry(d->ifd[EXIF_IFD_EXIF],t) : \
exif_content_get_entry(d->ifd[EXIF_IFD_GPS],t) ? \
exif_content_get_entry(d->ifd[EXIF_IFD_GPS],t) : \
exif_content_get_entry(d->ifd[EXIF_IFD_INTEROPERABILITY],t) ? \
exif_content_get_entry(d->ifd[EXIF_IFD_INTEROPERABILITY],t) : NULL)
#ifdef __cplusplus
}
#endif /* __cplusplus */
#endif /* __EXIF_DATA_H__ */
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